Educational abacus set



Filed Feb, 7, 1956 FIG-1- aol lnoaLO Unimd Sta s Patent EDUCATIONAL ABACUS SET Karl Hofmann, Wuerzburg, Germany, assignor of onehalf to Paul 0. Tobeler, doing business under the name of- Trans-Oceanic, Los Angeles, Calif.

Application February 7, 1956, Serial No. 563,999

6 Claims. (CI. 35-73) This invention relates to an educational abacus set and more particularly to an improvement upon the invention and structure shown and described in German PatentNo. 91 1,948.

In the educational abacus set shown in that patent the lid has a plurality of circular openings into which numbered tiles are placed. To cancel a problem and clear the board, the lid must be closed, causing the tiles to drop out of the openings. This is awkward in the case of a large set and does not take into consideration circum stances in which the teacher may Wish to cancel only part of the problem by removing only part of the tiles and leaving the remainder in place.

It is accordingly an object of my invention to provide a structure which is adaptable for use in a large set and in which some or all of the tiles may be removed, at the discretion of the user.

In accordance with the invention, the set includes at least one supporting board and at least one tile board. The supporting board, which may be the lid of the set, may be adjusted into an inclined position or may already assume an inclined position, in which it provides an inclined track for the number tiles. The openings to position the number tiles are not located in the sup-' the supporting board in such a manner that it may be 1 lifted therefrom for at least a distance equal to the thickness of the number tiles. Upon lifting of the number tile board, the number tiles can then readily fall, sliding downwardly along the sliding track provided by the supporting board, the latter being arranged with respect to the set receptacle so that the number tiles slide into the receptacle of the set.

If the openings are arranged in rows, the tileboard may be partially lifted to release or cancel only the lower row of number tiles and then further or completely lifted to release the upper row as well. Two tile boards may also be provided and interconnected to provide additional selectivity of board clearance.

The supporting board need not be the lid of the set, although this construction provides favorable results. It is merely required to assume a position inclined toward and suitable for observation by the students, in which position the tiles can readily be recognized without falling from their positioning openings. If the supporting board is a hinged lid, a positioning brace is provided therefor, which adjusts the supporting board in the inclined operating position upon the same plane, for example the table top, as the entire set. To preclude the sticking of the canceled tiles along the upper edge of the bottom part-of the set, the sliding surface formed by the supporting board is extended through a corresponding or equallyinclined sliding surface provided by the lower part of the set.

My invention also comprises such other objects, advantages and capabilities as will later more fully appear and which are inherently possessed by my invention.

2,840,927 "Patented July 1, 1958 While I have shown in the accompanying drawings a preferred embodiment of my invention, it should be understood that the same is susceptible ofmodification and change without departing from the spirit of my invention.

Referring to the drawings, Fig. 1 is a rear elevational view of my educational abacus set in closed position with the lid supporting bracket removed; 7

Fig. 2 is a top plan view of the same, with the tile openings and supporting bracket groove indicated in dotted lines;

Fig. 3 is a side elevational view of the same, With the supporting bracket and tiles shown in dotted lines;

Fig. 4 is a front view of the set in open position;

Fig. 5 is a sectional view of the set in open position with the supporting bracket in use and the movement of the lid and tiles indicated in dotted lines.

A preferred embodiment which has been selected to illustrate my invention comprises a substantially rectangular hollow box 10, having a rear wall 11 with an angularly inclined inner surface. A lid 12 is pivotally attached to the top of the rear wall 11 by a plurality of hinges 13. A pair of tile boards 14 and 15 are substantially equal in size to and overlie the inside ofthelid 12. The tile boards 14 and 15 are pivotally attached along one edge thereof to the front edge of the lid 12 by hinges 17 or other suitable means.

Each of the tile boards 14 and 15 is provided with a plurality of openings 16, which are arranged in rows. When the lid 12 is in open position, as shown in Figs. 4

and 5 of the drawings, its now upwardly directed inner surface provides a supporting board. The openings 16 in tile board 14 comprise two rows 13 and 19 and the openings in tile board 15 comprise two rows 20 and 21. Each row comprises a straight row of spaced openings.

In order to prevent excessive strain on the hinges 13, a supporting bracket 22 is provided, which is adapted to fit beneath and support the lid 12 when the same is in open position, as shown in Fig. 5 of the drawings. One edge of the supporting bracket 22 is dove-tailed, or otherwise chamfered to slidably fit into a groove 25 which extends across the top of the lid 12. The supporting bracket 22 is removable and is adapted to fit within the box 19 when not in use. Both positions of the supporting bracket 22 are shown in dotted lines in Fig. 3 of the drawings.

The bottom of the box it) and supporting bracket 22 are providde'd with small rubber legs 24, which are adapted to rest upon the supporting surface, such as a table top, and act to prevent displacement of this set.

Each of the openings 16' is adapted to removably receive and hold one of a plurality of identically formed number tiles 25, which rest upon the upwardly directed inner surface of the lid 12. The number tiles 25 are substantially disk-shaped and are stored in the box 10 when not in use.

The tile boards 14 and 15 are provided with small laterally projecting knobs 2s and 27 respectively, which may be manually grasped by the user to pivot the tile boards 14 and 15 upwardly as shown in dotted lines in Fig. 5 of the drawings. The tile boards 14 and 15 are inter-connected by a bracket 28, which is attached to tile board 14 and which fits beneath tile board 15. In this way, when tile board 14 is raised by means of its knob 26, tile board 15 is lifted simultaneously through the upward movement of bracket 28. On the other hand, if knob 27 is operated to lift tile board 15, tile board 14 will not be lifted. Instead of the bracket 28, the tile boards 14 and 15 may be connected by overlapping the adjacent edges of the tile boards so that the edge of tile board 15 overlaps the adjacent edge of tile board 14.

In use, the number tiles 25 are placed within the openment of knob 27 will clear both rows 20 and 21.

ings 16 in the tile boards 14 and 15. When the board is to be cleared, one of the knobs 26 or 27 may be raised to pivot one or both of the tile boards 14 and 15 upwardly and release the tiles 25 from the openings 16. Upon their release, the number tiles 25 will move downwardly along the lid 12 by force of gravity, passing beneath the tile boards 14 and 15 and falling into the hollow interior of the box 10. In this connection, it will be noted that the oblique inner surface of the rear wall 11 of the box forms a continuation of the lid 12, to facilitate the downward sliding movement of the number tiles 25.

It will also be noted that if the tile boards 14 and are lifted a short distance, only the number tiles which are held in the lower rows 18 .and 20 will be released. Upon further upward pivotal movement of the tile boards 14 and 15, the number tiles in the upper row 19 and 21 will be released.

This structure thus permits a considerable amount of selectivity in the use and clearing of the board. For example, a short upward movement of knob 27 will clear only row 20. A further upward movement of knob 27 will clear row 21. An initially greater move- A short movement of knob 26 will clear rows 18 and 20. A further upward movement of knob 26 will clear rows 19 and 21. An initially greater movement of knob 26 will clear the entire board.

This partial clearing of the board is helpful in teaching. For example, the upper rows 19 and 21 may be used to show the numbers from one to ten, while the lower rows 18 and 20 are used for the numbers from eleven to twenty. The teacher can cancel only the number series from eleven to twenty, which is less familiar to the student, while leaving the number series from one to ten intact.

Suitable means may be provided, if desired, to limit or regulate the pivotal movement of the tile boards 14 and 15. The number tiles may be printed in contrasting colors on their opposite faces to facilitate problem demonstrations through the use of color.

It is within the scope of the present invention that other suitable means may be used to release the tiles by providing openings through which the number tiles will move downwardly by the force of gravity.

1. An educational abacus set comprising a substantially rectangular box, said box having a hollow portion in the lower part thereof adapted to removably receive and hold a plurality of number tiles, said box having a pivotable lid, means for holding said lid in upwardly inclined position with respect to the hollow portion of said box, said lid having a substantially flat upper surface when held in such inclined position, a tile board pivotally attached to said lid, said tile board being normally disposed in overlying relationship to the upper surface of said lid, said tile board having a plurality of openings therein, each of said openings being adapted to receive and hold one of a plurality of number tiles in fixed position on said lid, said lid adapted to be pivoted to permit said tiles to be moved by force of gravity downwardly along the fiat inclined surface of said lid into the hollow portion of said box.

2. The structure as set forth in claim 1, the openings in said tile board being arranged in two vertically spaced rows, said tile board adapted to be pivoted a short distance upwardly to release the tiles held in the lower of said rows and pivoted a greater distance upwardly to release the tiles held in the row spaced upwardly therefrom.

3. The structure as set forth in claim 1, said tile board being divided into two laterally spaced sections, one of said sections adapted to be pivoted independently of the other to clear half of said tile board.

4, The structure as set forth in claim 1, said tile board being divided into two laterally spaced sections, one of said sections adapted to be pivoted independently of the other to clear half of said tile board, and means connected to said sections so that movement of the other section will move both of said sections simultaneously to clear all of said tile board.

5. The structure as set forth in claim 1, said box having on the inside thereof an inclined slide, said slide being upwardly inclined toward the pivotal connection of said lid, the inclination of said slide substantially corresponding to and constituting a continuation of the inclination of said lid, so that said slide facilitates the sliding movement of said number tiles into the hollow portion of said box.

6. The structure as set forth in claim 1 and a supporting bracket removably attached to said lid to support said lid in its inclined position, said bracket being smaller in size than and adapted to fit within the hollow portion I of said box.

References Cited in the file of this patent UNITED STATES PATENTS 

